1. Technical Field
This invention relates generally to a method and apparatus for providing switched packet data services between an electronic device and a network, and more particularly to a method and apparatus for enabling switched packet data transfer between the electronic device and one of a plurality of networks.
2. Background Art
In recent years, mobile telephones have enjoyed explosive growth in popularity. Once a luxury for only a few, today millions of people use mobile telephones to stay connected with friends, family, and coworkers. Coupled with the rise in popularity of mobile telephones has been an improvement in wireless communications networks. Older, analog systems have given way to new digital technologies and high capacity communication networks. Communication systems like Code Duplex Multiple Access (CDMA) and Global Systems for Mobile Devices (GSM) offer mobile telephone users reliable voice connections around the world.
In addition to voice communication, many mobile phones today are capable of exchanging packet data. For instance, phones capable of working in General Packet Radio Service (GPRS) systems are capable of exchanging packets of data between the mobile phone and a wireless network. General packet radio service devices, in addition to serving as traditional mobile telephones, are capable of exchanging text messages, pictures and sounds across the network. They are also capable of connecting to the Internet and World Wide Web.
While many wireless wide area network service providers offer switched packet data service through their cellular networks, the data transfer rates can be slow. Some service providers also charge additional fees for switched packet data service. Additionally, on occasion, the wide area network may be temporarily out of service. When any of these situations arises, it would be advantageous for a device to be able to establish a switched packet data connection with an alternate network. For example, if a wireless local area network (WLAN) were present, a device may be able to obtain higher transfer rates or functioning connections by transferring data with the wireless local area network rather than with the wide area network. Further, as base station transceivers in wireless local area networks are typically closer to a device than in wide area networks, battery power may be saved during communication with wireless local area networks as device transmission power can be reduced.
The problem with accomplishing this is that general packet radio service devices are generally configured to obtain data connections only from a service provider. In other words, in a general packet radio service system an electronic device establishes a switched packet data connection with what is known as a packet data protocol (PDP) context connection. The device, or an application within the device, does this by sending a packet data protocol-context initiation request to a servicing general packet radio service support node (SGSN). The request includes a service provider's programmed access point name (APN). A gateway general packet radio service support node (GGSN) then requests a dynamic Internet protocol (IP) address for the device. The gateway general packet radio service support node then assigns this dynamic IP address to the device so that a switched packet data connection may be established.
Therefore, unless the wireless local area network to which the device would like to connect includes a general packet radio service subnetwork that operates in conjunction with a service provider's access point name, the general packet radio service device will be unable to connect to the wireless local area network. There is thus a need for a method and apparatus for an electronic device, like a general packet radio service radiotelephone for example, to be able to establish switched packet data connections with alternate networks.
Skilled artisans will appreciate that elements in the figures are illustrated for simplicity and clarity and have not necessarily been drawn to scale. For example, the dimensions of some of the elements in the figures may be exaggerated relative to other elements to help to improve understanding of embodiments of the present invention.